Acid leaching of nickel from dunite rock

• Main Author: Appleyard, R. V.
• Language: en
• Published: University of Canterbury. Chemistry 2012
• Online Access: http://hdl.handle.net/10092/6955

It has been known for some time that the major component of Fun Mountain dunite (an almost pure olivine rock (Mg,Fe,Ni)₂SiO₄) is soluble in dilute mineral acide. However, the cost of reagents rules out an acid dissolution process as a source of nickel. Also the presence of large amounts of iron in a dilute nickel solution would introduce technological difficulties and adverse economic factors in the separation of these metals. Any efficient acid leaching process would need to selectively remove the nickel from the lattice in preference to magnesium and (particularly) iron. Such a requirement may be met if a secondary, essentially solid phase reaction took place in which cations in the lattice are substituted by protons without loss of lattice structure. Some experimental support for such a reaction has been forth-coming and the object of this research was an investigation into this lattice theory as well as a general review of the behaviour of dunite under the action of various acid leaching agents.